Oil pump NPA 64 based on the robotic principle.

Golovna

Fines

• The first hydraulic excavators appeared in the late 40s in the USA, as well as on tractors, and in England.
• At the FRN, in the mid-50s, hydraulic drives began to stagnate on both rotary (mounted) and rotary excavators.
• In the 60s, hydraulic excavators and hanging ropes began to be produced in all developed countries.
• This is explained by the basic advantage of hydraulic drive over mechanical drive.

The main advantages of hydraulic machines over cable machines are:

• significantly fewer excavators of the same size and dimensions; Significantly greater digging effort, which allows you to increase the filling of the shovel bucket at great depths, because The excavation resting on the ground is compressed by the weight of the entire excavator through the hydraulic cylinders of the boom;
• the ability to carry out earthling work in limited minds, especially in small minds, with the cessation of possession of all the digging that is being replaced; an increase in the number of changeable equipment, which allows you to expand the technological capabilities of the excavator and reduce the effort of manual work.
• The real advantage of hydraulic excavators is their design and technological power:
• The hydraulic drive can be configured as an individual leather drive mechanism, which allows the mechanisms to be assembled without binding to power plants, which will simplify the design of the excavator;

in a simple way transform the rotational flow of mechanisms into a progressive one, eliminating the kinematics of the operating equipment; stepless speed control;

In the USSR, the first hydraulic excavators began to be produced in 1955, the production of which was immediately organized in great efforts.

Rice. 1 Excavator-bulldozer E-153

Price based on MTZ tractors Hydraulic excavator E-151 with a bucket capacity of 0.15 m 3.

The hydraulic drive was provided by NV gear pumps and R-75 hydraulic pumps.

Then the E-153 excavators began to be produced to replace the E-151 (Fig. 1), and then the EO-2621 with a 0.25 m 3 bucket. There were specialized factories for the production of these excavators: Kiev “Chervony Excavator”, Zolotoustivsky Machine Building Plant, Saransk Excavator Plant, Borodyansky Excavator Plant. However, the availability of hydraulic conditions with high parameters, both for productivity and for working pressure, has driven the creation of rotary excavators.

Rice. 2 Excavator E-5015 In 1962, the family grew up in Moscow international exhibition everyday and road vehicles. At this exhibition, the English company demonstrated a crawler excavator with a 0.5 m3 bucket.

This machine has won admiration for its productivity, maneuverability, and light weight.

Galusia at that time did not have a base for hydraulic machines at all.

What can designers get for insurance?

These gear pumps NSh-10, NSh-32 and NSh-46 (Fig. 3) with a working volume of 10, 32 and 46 cm 3 / with a working pressure of up to 100 MPa, axial plunger pump-motors NPA-64 (Fig. 4) working volume 64 cm 3 /about and working vice 70 MPa and IIM-5 working volume 71 cm 3 /about working vice up to 150 kgf/cm2, high-torque axial piston hydraulic motors VGD-420 and VGD- 630 for torque and 630 kgm consistently.

Rice. 4 Pump-motor NPA-64

In the 1960s, Grechin N.K. It is requested to purchase from the company "K. Rauch" (FRN) a license for the production in the USSR of hydraulic equipment: axial plunger control pumps of type 207.20, 207.25 and 207.32 with maximum operating volume torque 54.8, 107, and 225 cm 250 kgf/cm2, twin axial piston control pumps type 223.20 and 223.25 with a maximum working volume of 54.8 + 54.8 and 107 + 107 cm 3 / rev and short-hour pressure up to 250 kgf / cm2 similar to type 210.12, 10.16, 210.20, 210.25 and 210.32 for workers volume 11.6, 28.1, 54.8, 107 and 225 z m 3/rev and short-hour pressure up to 250 kgf/pressure, regulators etc.). Also, equipment is purchased for the generation of hydroelectricity, although not in a completely unnecessary manner and nomenclature.

Dzherelo photo: tehnoniki.ru

Vinyatkov’s role in the rebuilt factories and their specialization was played by the First Protector of the Minister of Public Works, Roads and Municipal Engineering V.K. Rostotsky, who supported N.K. Grechin with his authority.

in the production of hydraulic machines. Ale in opponents Grechin N.K. Seriously, where are we going to get drivers and mechanics who operate hydraulic machines?

A group of new specialties was organized at the vocational schools, machine manufacturers carried out training for excavators, repairmen, etc.

The school "Vishcha School" has taken over the chief employees from these machines.

From whom the spіvrobіtniki of VNDІbuddormash gave great help, as they wrote great amount.

chief subsidiaries on Qiu topics. Thus, the excavator factories of Kovrovsky, Tversky (Kalininsky), Voronezky will switch to the production of advanced machines with hydraulic drives, replacing mechanical ones with cable drives.

Piston pumps and hydraulic motors of excavators

The pump consists of an indestructible split disk 7, a block 2 that wraps around, 3 pistons, 4 rods and a small disk 5, hinged to the rod 4. The split disc 7 has a broken arc hole 7 (Fig. 105, g), through yaki The home will smoke and pump with pistons.

Between the windows there are 7 transfer bridges of width bt to reinforce the empty discharge head.

When the block is wrapped, the 8 cylinders are connected to either the empty winding or the empty charging.

When changing the direction, the wrapping of the function block 2 empties changes.
To change the threads from the middle, carefully rub the end surface of block 2 up to the split disk 5. Disk 5 wraps around shaft 6, and at the same time block 2 cylinders wraps around the disk.

The pump flow per shaft revolution is 64 cm3.

At 1500 rpm of the shaft and the working vice of 70 kgf/cm2, the pump flow is set to 96 l/cm2, and the volumetric pressure factor is 0.98.

In the NPA-64 pump, the entire cylinder block is moved from the cut to the axis of the conductor shaft, which means it is called a bad block.

In the case of axial pumps with a rotating disc, the entire cylinder block is connected to the entire drive shaft, and underneath it the entire disc is retracted, to which the piston rods are articulated c.

Let's take a look at the design of an adjustable axial piston pump with a thin disc (Fig. 108). і pump flow adjust by changing the disc angle to match the 8-cylinder block 3.

105 Schemes of an axial piston pump:

A - dii piston,
B - pump robot, - constructive, d - part of an indestructible spreading disk;

1 - non-coloured split disk,

2 - block that turns around.

3 - piston,

5 - sick disk,

7 - arc window,
8 - cylindrical opening;
A - the end of the full cut of the arc window
106 Diagram of an adjustable axial piston pump:
1 - washer,
2 - plunger,

3 - shaft,

4 - piston,

5 - spring Spherical bearings have a large disk 6 and pistons 4 secured by the ends of the connecting rod 5. During operation, the connecting rod 5 moves to a small angle along the cylinder axis J, so the actual storage force that acts on the bottom of the piston 4 is insignificant. The torque on the cylinder block is determined only by the rubbing end of the block 8, the split disk 9. The magnitude of the moment lies under the vice in the cylinders 3. Almost all the torque from shaft 2 is transmitted to the small disk 6, since when it is turned pistons 4 are located, working in the air with cylinders 3. Therefore, the most important element in such pumps is the cardan mechanism 7, which transmits all the torque from shaft 2 to disk 6. The cardan mechanism surrounds the heel of disk 6 and increases the dimensions of the pump.

Block 8 of the cylinders is connected to shaft 2 through mechanism 7, which allows the block to self-align on the surface of the spacer disk 9 and transmit the rubbing torque between the ends of the disk and the block to shaft 2. One

The working center of the hydraulic system is the pumping group.

The pump group consists of two axial plunger pumps NPA-64 and moves a cylindrical gearbox, which ensures the nominal speed of the pump shaft wrapping - 1530 rpm.

Such a fluidity, with a pump productivity of 64 cm3/hw, will ensure a supply of 96 l/hw to the hydraulic system to the hydraulic elements (power cylinders) of the left pump and 42.5 l/hw of the right pump.

The selection of tension for driving the pumps is done from the tractor gearbox behind the auxiliary gearbox that drives.

The gearbox has a cast iron body, which is attached with flanges to the front part of the tractor transmission housing, left-handed in the direction of the rest.

1. A cylindrical gear sits on the primary splined shaft, which is inserted into the gear of the tractor drive pulley and the gearbox shaft.
2. There are three stages of adjusting the gearbox.
3. As the primary roller and gear shaft wrap around, the pumps work.

If the roller is wrapped and the gear shaft is locked, there is only one pump.

Since the head gear of the gearbox is removed from its engagement with the gear of the tractor drive pulley, the pumps are not damaged.

The tightening and tightening of the gearbox is achieved by turning the valve connected to the control shaft. The pumps are mounted on the gearbox housing. The pumps are put into operation from the tractor gearbox and supply the working fluid from the oil tank (capacity 200 l) under a pressure of 75 kg/cm2 through the steam generators at the power cylinders.

From the power cylinders, the oil that was processed flows through the filters back into the tank.

Direct the hydraulic pump lower (

Rice. 45

).

A flange 7 is bolted to the pump housing 1, closed with a cover 11. The housing has a drive shaft 3 with pistons on bearing mountings.

The drive shaft with its polished part 3 is connected to the gearbox and is removed from the rest of the wrapping.

The cylinder block 10 removes the wrapping from the drive shaft behind the auxiliary cardan 6.

When the axis of the cylinder block is pressed against the axis of the drive shaft, piston 16, when the block is wrapped, a reciprocating rotation occurs.

This is where it is necessary to lay down the rest of the piston stroke and, therefore, its productivity.

This pump has a constant pressure and a maximum of 30°.

To explain the principle of a robotic pump, let’s look at a robot with only one piston.

Piston 16 makes one revolution of the cylinder block, one stroke.

The extreme left and right positions indicate the cob being wound up and pumped.

When turning the piston to the left (with the block wrapped behind the year arrow), re-winding occurs, when turning to the right - injection.

The position of the installation and injection is adjusted to the opening of the opening 14 so that the grooves are installed and the injection (the grooves are oval, the stench is not visible to the baby) of the distributor 15.

During the installation process, the opening of the block 14 takes a position opposite the grooves for the installation of the distributor, connected to the installation channel.

When pressurized, hole 14 occupies a position opposite the injection grooves, which are connected to the injection channel. At the same time, the other six pistons operate in a similar way. When the pump is empty during operation, the oil is discharged into the operating tank through drainage hole 5. The movement of the vice is allowed to be surrounded by two locking valves installed on the skin pump. Hydraulic cylinders are used for the operation of all parts of the working parts of the excavator.

On

excavators E-153A

nine cylinders installed (

Rice. 47 ) piston type with a straight reciprocating rod. When the rod collapses, one empty cylinder connects to the pump, and the other - to the drain line.

Directly, the movement of the rod is indicated by the importance of the hydraulic system control box.

The bulldozer cylinder additionally has a split in the middle of the pipe.

Additional threading is necessary for fastening the traverse with trunnions (Fig. 76). ) piston type with a straight reciprocating rod. Rods of 29 cylinders of the boom, handle, bucket and turning mechanism (

) are hollow and consist of pipe 28, shank 13 and pipe 21, welded together.

The rods of other cylinders are made from solid metal.

The cylinder rod collapses at the bronze bushing 24 of the front cover.

For better wear resistance and anti-corrosion properties, the working surface of the rod is chrome-plated.

On the free shank of the landing rod there is a piston 9 with two 10 cuffs, supported by stops 11 and a cone 12.

The cone together with the ring creates a damper, which serves to cushion the impact at the end of the stroke when the rod is hanging in the extreme position.

The piston, stops and cone are secured with a nut 4 and a lock washer 3.

Piston 9 has ledges on both sides to accommodate cuffs 16. In the middle of the piston there is an annular groove with a groove 2, which serves to ensure flow from one empty cylinder to the according to the stock.

On the shank of the rod there is a housing, which, when in the extreme left position, enters the opening of the rear cover and creates a damper that softens the impact at the end of the stroke.

The piston serves as a support for the rod, and at the same time, thanks to the reinforcements, it reliably divides the cylinder into two empty parts, one of which receives oil, and the other.

The rear covers of all cylinders, behind the barrel of the bulldozer cylinder, are blind and at their tail part there is an ear with a pressed sealed bushing 6 for the articulated connection of the cylinder.

The threaded part of the cover has an annular groove with a squeezer ring 8, which serves to draw the threads from the cylinder.

The rear cover of the bulldozer cylinder has a central cross-cut connection for connecting the main part through a fitting and fastening it to the cover with bolts.

The rear covers of the boom cylinders, handles, buckets and supporting shoes are centrally and centrally drilled to connect with each other and create a working channel.

The front cover 27 is screwed onto the pipe.

For the passage of the rod in the crack, there is an opening with a bronze bushing 24 pressed into it. In the middle of the cover there are two ledges: the first rests on the cuff 16, is supported against axial displacement by the collar ring 25 and locking spring rings eat 26;

on the other, the ring 14 rests, which, together with the cone 12, presses against the damper rod and separates the overflow of the piston.

On the other side, the cap 18 is screwed onto the front cover, which holds the washer 19 and the hammer 20.

On the side of the screen there is an opening for transferring the liquid through the fitting.

All the covers have slots for the key and are locked with locknuts. The movement of the vice is allowed to be surrounded by two locking valves installed on the skin pump. The end fitting is attached to the cylinder with bolts and reinforced with a gum ring 15.

• For uninterrupted operation of the hydraulic cylinders, promptly replace the wear and tear parts.
• Make sure that the cylinder rods are not damaged or damaged.
• Periodically tighten the connections of the fittings, as if there is a gap between the fitting and the clamp, the tightening will quickly result.
• Hydraulic distributors and control boxes are the main components of the excavator control mechanisms.
• They are designated for the division of the working unit, which goes from living hydraulic pumps to power cylinders, of which there are nine on the excavator (
• ).

All the stinks have their own meaning: The movement of the vice is allowed to be surrounded by two locking valves installed on the skin pump. a) the cylinder of the arrow is used for lifting and lowering;

The right box, connected to the right rear pump, distributes the working core along the cylinders of the handle, bucket and bulldozer.

This box has a double shunt spool;

There is one locking valve 6 and two locking valves 7 and 8. In other respects, the design of the boxes is the same. The movement of the vice is allowed to be surrounded by two locking valves installed on the skin pump. To operate one of the excavator mechanisms, it is necessary to move the throttle-spool pair up or down, depending on which mechanism is responsible for moving.

The left control valve is a throttle, which changes the flow of oil directly, and the right control valve is a spool valve, which changes the flow of oil directly.

Oil tank 17 (

) is a stamped-welded structure made of sheet steel with a thickness of 1.5 mm.

It consists of a straight-cut body, in the middle of which several partitions are welded, designed for a quiet working environment and emulsion distribution.

The top of the tank is closed with a stamped lid and a gasket with oil-resistant gum.

In the center of the lid there is a straight hole into which the filter tank 12 is inserted, which serves for partial cleaning of the oil.

There are two welded fittings at the bottom of the tank, through which oil flows from the pump, and there is an opening, closed with a plug, through which, if necessary, oil flows out of the tank. Three cylindrical filters are inserted into the sides of the tank. The tank has an observation window 10, which allows you to stitch along the working line near the tank. The final turns 11 direct the flow of the working fluid and increase its fluidity. Isolation valve 8 at the filter tank and regulation at a pressure of 1.5 kg/cm2.

All elements of the hydraulic system - pipes, hoses - are connected to each other using fitting connections 7 ( ) piston type with a straight reciprocating rod.).